Material handling system and method thereof

Abstract

A material handling system includes: a frame defining a first axis; a plurality of suction units coupled to the frame and distributed in rotational symmetry about the first axis; and at least one stopper. The plurality of suction units collectively defines a distal plane normal to the first axis, with each of the plurality of suction units being operable to provide a suction force in a suction direction parallel to the first axis. The at least one stopper is fixedly coupled to the frame and extends beyond the distal plane to provide one or more abutment ends disposed stationary relative to the frame. The one or more abutment ends define a transverse offset axis extending through all of the one or more abutment ends. The transverse offset axis is a straight line spaced apart from the first axis and parallel to the distal plane.

1 . A material handling system, comprising:
 a frame defining a first axis;   a plurality of suction units coupled to the frame and distributed in rotational symmetry about the first axis, the plurality of suction units collectively defining a distal plane normal to the first axis, each of the plurality of suction units being operable to provide a suction force in a suction direction parallel to the first axis; and   at least one stopper, the at least one stopper being fixedly coupled to the frame and extending beyond the distal plane to provide one or more abutment ends disposed stationary relative to the frame, the one or more abutment ends defining a transverse offset axis extending through all of the one or more abutment ends, wherein the transverse offset axis is a straight line spaced apart from the first axis and parallel to the distal plane.   
     
     
         2 . The material handling system as recited in  claim 1 , comprising a controller coupled to the plurality of suction units, the controller being configured to control any one of the plurality of suction units independently of any other of the plurality of suction units. 
     
     
         3 . The material handling system as recited in  claim 2 , wherein the plurality of suction units are controllable independently of one another to provide a variable net suction force in the suction direction. 
     
     
         4 . The material handling system as recited in  claim 2 , wherein the frame defines a plurality of chambers, each of the plurality of suction units comprises a fan disposed in a respective one of the chambers, the fan being controllable by the controller to operate in any one of two directions to provide a torque in a corresponding one of two torque directions. 
     
     
         5 . The material handling system as recited in  claim 4 , wherein the plurality of suction units are controllable independently of one another to provide a variable net torque. 
     
     
         6 . The material handling system as recited in  claim 2 , comprising a distance sensor coupled to the frame, wherein the distance sensor is disposed spaced apart from any one of the at least one stopper. 
     
     
         7 . The material handling system as recited in  claim 6 , wherein the distance sensor is disposed diametrically opposite the transverse offset axis. 
     
     
         8 . The material handling system as recited in  claim 2 , comprising an inertial measurement unit coupled to the frame, wherein the inertial measurement unit is configured to measure at least one kinematics parameter of the frame. 
     
     
         9 . The material handling system as recited in  claim 8 , wherein the controller is configured to independently control the plurality of suction units based on the at least one kinematics parameter of the frame. 
     
     
         10 . The material handling system as recited in  claim 2 , wherein the plurality of suction units in operation provides a suction force on a workpiece in the suction direction towards the distal plane, and wherein a workpiece surface of the workpiece facing the distal plane is spaced apart from the distal plane by an abutment of the one or more abutment ends with a workpiece edge of the workpiece. 
     
     
         11 . The material handling system as recited in  claim 10 , wherein the controller is configured to controllably vary a spacing between the workpiece surface and the distal plane by varying a respective suction force of each of the plurality of suction units. 
     
     
         12 . The material handling system as recited in  claim 10 , wherein the plurality of suction units comprises four suction units distributed in rotational symmetry about the first axis, and wherein the controller is configured to operate two diametrically opposing ones of the four suction units to produce respective clockwise torque, and wherein the controller is configured to operate another two diametrically opposing ones of the four section units to produce respective anti-clockwise torque. 
     
     
         13 . The material handling system as recited in  claim 10 , wherein the frame comprises a straight side, and wherein the at least one stopper comprises two stoppers coupled to the straight side such that each one of the two stoppers forms a point contact with the workpiece edge. 
     
     
         14 . The material handling system as recited in  claim 10 , wherein the controller is configured to control each of the plurality of suction units to produce a respective suction force and a respective torque, and wherein each of the respective suction force and the respective torque of any one of the plurality of suction units is independent of forces produced by any other of the plurality of suction units. 
     
     
         15 . The material handling system as recited in  claim 14 , wherein the controller is configured to control the plurality of suction units based on any one or more of the following: (i) a target trajectory of an angle between the workpiece surface and the distal plane, (ii) a target contact force between the workpiece and the at least one stopper, (iii) a target contact torque between the workpiece edge and the at least one stopper, and (iv) at least one kinematics parameter of the frame. 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
         20 . The material handling system as recited in  claim 15 , wherein the target contact torque is zero. 
     
     
         21 . (canceled) 
     
     
         22 . The material handling system as recited in  claim 14 , wherein the controller is configured to vary a contact force and a contact torque by controlling at least one of the respective torque, and wherein the contact force and the contact torque are at an interface between the workpiece edge and the at least one stopper. 
     
     
         23 . A method of controlling a material handling system, comprising:
 controlling a plurality of suction units coupled to a frame to provide a suction force on a workpiece surface of a workpiece in a suction direction parallel to a first axis, the plurality of suction units being distributed in rotational symmetry about the first axis and collectively defining a distal plane normal to the first axis; and   providing at least one stopper in abutment with a workpiece edge of the workpiece, the at least one stopper being fixedly coupled to the frame and extending beyond the distal plane to provide one or more abutment ends disposed stationary relative to the frame, the one or more abutment ends defining a transverse offset axis extending through all of the one or more abutment ends, wherein the transverse offset axis is a straight line spaced apart from the first axis and parallel to the distal plane.   
     
     
         24 . The method as recited in  claim 23 , wherein each one of the plurality of suction units is controlled independently of any other of the plurality of suction units to keep the workpiece surface spaced apart from the distal plane by a spacing, wherein the spacing is controllably variable by varying a respective suction force of each of the plurality of suction units. 
     
     
         25 . The method as recited in  claim 24 , wherein each one of the plurality of suction units is controlled based on any one or more of the following: (i) a target trajectory of an angle between the workpiece surface and the distal plane, (ii) a target contact force between the workpiece and the at least one stopper, (iii) a target contact torque between the workpiece and the at least one stopper, (iv) at least one kinematics parameter of the frame.